Patent GB-475559-A (GB)
Title: Process for the manufacture of pyramidine compounds
Filed: 1936-05-19
Abstract: 2-Alkyl-(or 2-aralkyl)-4-amino-5-aminoalkylpyrimidines are prepared as follows.  An amidine of an aliphatic or araliphatic carboxylic acid is condensed with an acetonitrile derivative substituted by (a) a hydroxymethylene group, an etherified hydroxymethylene group, or a carboxylic ester group, and (b) a protected aminoalkyl group or a group (as defined below) convertible into an aminoalkyl group.  When substituent (a) is a hydroxymethylene or an etherified hydroxymethylene group, the reaction yields a 2 - alkyl - (or 2 - aralkyl) - 4 - aminopyrimidine substituted in the 5-position with a substituent as at (b) above, and this product is treated to convert the substituent in the 5-position into an aminoalkyl group.  When substituent (a) is a carboxylic ester group, the reaction yields a 2-alkyl-(or 2-aralkyl)-4-amino-6-hydroxypyrimidine (or the corresponding tautomeric 6-oxo compound) substituted in the 5-position with a substituent as at (b) above; this product is treated to replace the substituent in the 6-position successively by halogen and hydrogen, e.g. by the successive action of a phosphorus halide and a reducing agent such as zinc dust, and the substituent in the 5-position is then treated to convert it into an aminoalkyl group. The substituent as at (b) above may be an acylaminoalkyl group or any of the following: a carboxylic acid ester or amide group, an alkylcarboxylic acid or ester group, a cyano or cyanoalkyl group, or an alkoxyalkyl group.  An alkylcarboxylic acid or ester group may be converted into an aminoalkyl group by way of the alkylcarboxylic amide or hydrazide group, which may then be degraded in known manner, e.g. by the Hoffmann or Curtius reaction.  A carboxylic ester group may be converted into an aminoalkyl group by way of the carboxylic amide group, which is converted into a cyano group and then reduced. A cyanoalkyl group is converted into an aminoalkyl group by reduction.  An alkoxyalkyl group may be converted into an aminoalkyl group by way of a halogenalkyl group.  In the examples: (1) acetamidine hydrochloride and cyanosuccinic acid diethyl ester yield 2 - methyl - 4 - amino - 6 - hydroxypyrimidine-5-acetic ester, which is treated successively with phosphorus oxychloride and zinc dust to yield 2-methyl-4-aminopyrimidine-5-acetic ester; the latter is treated with ammonia in methyl alcohol to yield 2-methyl-4-aminopyrimidine-5-acetamide, which is converted into 2-methyl-4-amino-5-aminomethylpyrimidine as described in Specification 473,193; (2) acetamidine hydrochloride and ethoxymethylenemalonic acid dinitrile yield 2-methyl-4-amino-5-cyanopyrimidine, which is hydrogenated to yield 2-methyl-4-amino-5-aminomethylpyrimidine; if propionamidine is used in place of acetamidine, 2-ethyl-4-amino-5-cyano-and 2-ethyl-4-amino-5-aminomethyl-pyrimidine are obtained; (3) phenylacetamidine hydrochloride and cyanosuccinic acid diethyl ester yield 2-benzyl-4-amino-6-hydroxypyrimidine-5-acetic ester, which is treated with phosphorus oxychloride to yield 2-benzyl-4-amino-6-chloropyrimidine-5-acetic ester; the latter, by treatment with zinc dust, yields 2-benzyl-4-aminopyrimidine-5-acetic ester, from which, by treatment with ammonia in methyl alcohol, 2-benzyl-4-aminopyrimidine-5-acetamide is obtained, and is converted into 2-benzyl-4-amino-5-aminomethylpyrimidine as described in Specification 473,193; (4) phenylacetamidine hydrochloride and ethoxymethylenemalonic acid dinitrile yield 2-benzyl-4-amino-5-cyanopyrimidine, which is hydrogenated to yield 2-benzyl-4-amino-5-aminomethylpyrimidine; (5) cyanacetic ester is treated with bromoethylphthalimide to yield phthalimidoethyl-cyanacetic ester, and the latter is condensed with acetamidine hydrochloride to yield 2-methyl-4-amino - 5 - phthalimidoethyl - 6 - hydroxypyrimidine; the latter, by treatment with phosphorus oxychloride, yields 2-methyl-4-amino-5-phthalimidoethyl-6-chloropyrimidine, which is treated successively with hydrazine hydrate and hydrochloric acid to yield 2-methyl-4-amino-5-aminoethyl-6-hydrazinopyrimidine; the latter, by treatment with copper sulphate in sulphuric acid solution, yields 2-methyl-4-amino-5-aminoethylpyrimidine.